Answer:
(4, 5 )
Step-by-step explanation:
x + y = 9 → (1)
x - y = - 1 → (2)
adding the 2 equations term by term will eliminate y
2x + 0 = 8
2x = 8 ( divide both sides by 2 )
x = 4
substitute x = 4 into either of the 2 equations and solve for y
substituting into (1)
4 + y = 9 ( subtract 4 from both sides )
y = 5
solution is (4, 5 )
4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50
Step-by-step explanation:
Some expressions that are equivalent to this is: 1 - 1/5; 2 - 1 1/5; 3 - 2 1/5; etc.
Answer:
93
Step-by-step explanation:
The average is calculated as
average =
On 3 quizzes
= 73 ( multiply both sides by 3 )
sum = 219
On 4 quizzes, letting x be the score on fourth test
= 78 ( multiply both sides by 4 )
sum + x = 312 , that is
219 + x = 312 ( subtract 219 from both sides )
x = 93
She must score 93 on the next quiz